and many more benefits!

Find us on Facebook

GMAT Club Timer Informer

Hi GMATClubber!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

Hide Tags

Show Tags

08 Jan 2008, 05:10

5

This post wasBOOKMARKED

00:00

A

B

C

D

E

Difficulty:

95% (hard)

Question Stats:

48%(02:52) correct
52%(01:34) wrong based on 117 sessions

HideShow timer Statistics

The figure attached shows the dimensions of a semicircular cross section of a one-way tunnel. The single traffic lane is 12 feet wide and is equidistant from the sides of the tunnel. If vehicles must clear the top of the tunnel by at least ½ foot when they are inside the traffic lane, what should be the limit on the height of vehicles that are allowed to use the tunnel?

Show Tags

08 Jan 2008, 06:15

Are they asking for the height of the tunnel at the EDGE of the 12 foot lane? or the height of the tunnel in the center? It's kind of vague, but I would assume they want the height of the tunnel at it's highest point (even though this isn't entirely practical, but perhaps that's where the 1/2 foot of tolerance comes in).

Show Tags

08 Jan 2008, 06:48

eschn3am wrote:

Are they asking for the height of the tunnel at the EDGE of the 12 foot lane? or the height of the tunnel in the center? It's kind of vague, but I would assume they want the height of the tunnel at it's highest point (even though this isn't entirely practical, but perhaps that's where the 1/2 foot of tolerance comes in).

Show Tags

08 Jan 2008, 07:07

1

This post receivedKUDOS

That does make more sense (since automobiles aren't 2D ).

In that case:

Answer B

Create a right triangle using the radius of 10 as a hypotenuse. The legs of the triangle will be 6 (1/2 of the travel lane) and X (the height at the edge of the road). 3-4-5 right triangle gives us a height of 8' at the side of the road. 8-.5 = 7.5' max

Show Tags

08 Jan 2008, 08:12

eschn3am wrote:

That does make more sense (since automobiles aren't 2D ).

In that case:

Answer B

Create a right triangle using the radius of 10 as a hypotenuse. The legs of the triangle will be 6 (1/2 of the travel lane) and X (the height at the edge of the road). 3-4-5 right triangle gives us a height of 8' at the side of the road. 8-.5 = 7.5' max

great, I agree with you) tellingly I never hit the right answer I am always close to it but it doesn't make me happy because real GMAT exam makes sever punishments for wrong answers whether it is close to right answer or not. what would you suggest me to do in order to decrease errors and increase precision? not to rush?

Show Tags

08 Jan 2008, 08:20

kazakhb wrote:

eschn3am wrote:

That does make more sense (since automobiles aren't 2D ).

In that case:

Answer B

Create a right triangle using the radius of 10 as a hypotenuse. The legs of the triangle will be 6 (1/2 of the travel lane) and X (the height at the edge of the road). 3-4-5 right triangle gives us a height of 8' at the side of the road. 8-.5 = 7.5' max

great, I agree with you) tellingly I never hit the right answer I am always close to it but it doesn't make me happy because real GMAT exam makes sever punishments for wrong answers whether it is close to right answer or not. what would you suggest me to do in order to decrease errors and increase precision? [b]not to rush[b/]?

that's it in a nutshell. Slow down, double check your work and draw out a diagram when doing geometry problems. I find I do much better on the Club Challenges when I slow down a bit. After awhile you'll know all the math you need, it's just eliminating stupid mistakes.

Show Tags

08 Jan 2008, 08:37

eschn3am wrote:

That does make more sense (since automobiles aren't 2D ).

In that case:

Answer B

Create a right triangle using the radius of 10 as a hypotenuse. The legs of the triangle will be 6 (1/2 of the travel lane) and X (the height at the edge of the road). 3-4-5 right triangle gives us a height of 8' at the side of the road. 8-.5 = 7.5' max

Show Tags

08 Jan 2008, 09:44

akhi wrote:

eschn3am wrote:

That does make more sense (since automobiles aren't 2D ).

In that case:

Answer B

Create a right triangle using the radius of 10 as a hypotenuse. The legs of the triangle will be 6 (1/2 of the travel lane) and X (the height at the edge of the road). 3-4-5 right triangle gives us a height of 8' at the side of the road. 8-.5 = 7.5' max

correct! ...7.5' for me too..

OA is B.

This kind of questions are easy to solve reading the text well because the are written in a tricky way! I answered D too...

Re: The figure above shows the dimensions of a semicircular [#permalink]

Show Tags

30 Nov 2013, 12:50

Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

Show Tags

The figure attached shows the dimensions of a semicircular cross section of a one-way tunnel. The single traffic lane is 12 feet wide and is equidistant from the sides of the tunnel. If vehicles must clear the top of the tunnel by at least ½ foot when they are inside the traffic lane, what should be the limit on the height of vehicles that are allowed to use the tunnel?

A. 5½ ft B. 7½ ft C. 8 ½ ft D. 9½ ft E. 10 ft

See the diagram attached:Rectangle inscribed has the length of traffic lane 12. So max height of vehicle will be 1/2 foot less than the width of this rectangle.

Now, let O be the center of the semi-circle, then OA=radius=20/2=10 and OB=12/2=6 --> \(AB=\sqrt{OA^2-OB^2}=\sqrt{10^2-6^2}=8\).

So max height of the vehicle that are allowed to use the tunnel is 8-0.5=7.5.